Ответ:

  1. Переставим слагаемые: 38 + 62 + 45 = 100 + 45 = 145.
  2. 75 + 25 + 28 = 100 + 28 = 128.
  3. 43 + 57 + 19 = 100 + 19 = 119.
  4. 125 + 75 + 48 = 200 + 48 = 248.
  5. (4 × 25) × 7 = 100 × 7 = 700.
  6. (6 × 5) × 13 = 30 × 13 = 390.
  7. 18 × (5 × 2) = 18 × 10 = 180.
  8. 16 × 20 + 16 × 3 = 320 + 48 = 368.
  9. 12 × 30 − 12 × 2 = 360 − 24 = 336.
  10. 27 × (4 + 6) = 27 × 10 = 270.
  11. (35 + 65) × 8 = 100 × 8 = 800.
  12. 600 ÷ 6 = 100.
  13. 600 ÷ 6 = 100.
  14. (42 ÷ 7) × 5 = 6 × 5 = 30.
  15. (720 + 80) ÷ 8 = 800 ÷ 8 = 100.